Gang-saw mill.



" w. M. WILKIN; GANG SAW MILL.

vAPPLIOATIr'gifHLmJ"MAY s, woz,

110 MODEL.v

PATENTED JUNE 2,v 1903;

Y4 SHEETS-SHEET 1.

'y No. 730,063.

W. M. WILKIN.

GANG SAW MILL.

-APPLIOATION FILED .MAY 6, 1902.

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PATBNTEDJUNE 2, y1903;

No MODEL.

fw. M. WILKIN. GANG SAW MILL. APPLIoATIoN FIL-BD MAY 6,1002. A 0 I yngrssnmr s.

PATENTED YJUNE 2,1003.,

PATENTED JUNE 2, 1903.-

. W. M. WILKIN.

' GANG SAW MILL. f APPLOATION FILED MAY 6,-1902. l v N0 MODEL. A {SHEETS-SHEET 4.

.i f l ysuch as will enable others skilled in the art vis frequently experienced in maintaining its Patented J une 2,?11903.

PATENT OFFICE. f

WILLIAM M. WILKIN, OF MOBILE, ALABAMA.

GANG-SAW MILL..

SPECIFICATION forming part of'Letters Patent N o. 730,063, dated June 2, 1903.

Application iiled May 6, 1902. Serial No. 106,152. (No model.) Y

To @ZZ whom. it may concern: f

Be it known that I, WILLIAM M. WILKIN, a citizen of the United States, residing at Mobile, in the county of Mobile and State of Alabama, have invented certain new and useful Improvements in Gang-Saw. Mills; and I' dol hereby declare the following to be a full, clear, and exact description of the invention,

to which it appertains to make and yuse the same, reference being had to the accompanying drawings, and to the letters 'of yreference marked thereon, forming part of this specification.

My invention relates to improvements in gang-saw mills, and has for its object the overcoming of defects in the construction and operation of gang-saw mills as now made and improvements in the construction thereof by means whereof I have greatly increased the capacity and improved the efficiency of the mill without materially increasing its weight and the cost of its construction.

The features of myimprovements consist substantially of the following, viz:

First. In constructinga gang-sawsash wid enough to saw two logs or cants at once and with a central support between the upper and lower girths ofthe sash, whereby I am enabled to use a wide sash of but little more weight than that of an ordinary narrow sash, and on this support I provide a series of cutters or choppers adapted to cut away any projecting parts on the logs or cants passing therethrough, so as to prevent'their contacting with said central support.

Second. In the operation of balanced gangs it is usual to provide a crank-shaft having U-shaped cran ks in opposite directions, a pitman leading from one crank to the lower girth of the saw-sash, and a pitman leading from the opposite4 crank to a counterbalance-weight. This construction necessitates a heavy shaft, as the wrist-pins of the cranks are necessarily a considerable distance apart longitudinally, and the strain of the work on the shaft necessarily. causes it to vibrate, so that difficulty bearings in proper condition, and when four cranks and pitmen are used, as is necessary with wide saw-sashes, as in this-case, this difficulty is greatly increased. In my construction I have reduced these diiiiculties to a minimum by utilizing eccentrics instead of gether on the shaft and, preferably, are made integral. By this means I am enabled to bring the lines of travel of the sash and weight -pitmen close together, thereby reducing the vibration. of the shaft to a minimum amount, 6o which enables me to use a comparatively small shaft, the bearings of which are easily kept in order. y

Third. In the construction of the press-rolloperating mechanism of gang-saw mills screw mechanism is ordinarily used; but it has been found desirable to operate them by means of steam or compressed-air cylinders; but as they have heretofore been constructed the cylinders were placed on the top of the mill- -7o frame and connected directly to the press-roll yoke. This construction not only greatly increased the weight of the structure, but so largely increased the height and weight of the ytop thereof that the vibration thereof, caused bythe rapidly1noving sash, has been uniformly so destructive to the structure, and as the pistons of the cylinders were connected with the center of the press-roll yoke the yoke would tilt and bind in its guides, so as 8o not to operate satisfactorily, which difficulties i have prevented its use to any extent, though a rapid means of handling the press-rolls is greatly desired. I have overcome these difficulties by placing the cylinders near the base on side of the lower part of the gang-saw frame and connected their pistons with arms on rock-shafts, and from other arms on said rock-shafts linksV extend to the ends of the press-roll yoke, to which they are detachably 9o connected, so that they can be disconnected and the press-roll mechanism swung back out of the way, so as to permit ready access to the sash. The arms on the rock-shaft, from which the links extend to the, ends of the press-roll yoke, I preferably make adjustable in length, so that if more pressure on the press-rolls is at any time desired the adjustable rock-shaft arms can be shortened and increased pressure thereby transmitted to the Ioo press-rolls.

Fourth. Gang-saw mills are largely used for resawing cants or ditches which have been previously squared on two or more of their cranks, which eccentrics are secured close to- 55 l .1 ...matte sides, which cants or flitches are placed on the saw-carriage with one of the square faces thereof in contact with guides at the sides of the carriage. IIeretofore it has been found diiiicult, if not impossible, to keep the cants or litches constantly in contact with these carriage-guides, and as a result thereof the outside cut from the cant or ditch is nearly always of unequal thickness at its ends, and therefore not marketable lumber, and to overcome this difficulty I provide the carriage with a pair of diagonal or cut rolls, having teeth adapted to engage the under surface of the rant, which rolls are mounted on movable hearings, by tneans whereof the rolls can be raised into contact with the cant or flitch or lowered away therefrom at the will of the op-A erator. These diagonal or cut rolls operate as the cants or tiitches move over them to constantly carry the cant or tlitch toward and against the saw-carriage guides, so that as the cant or flitch passes the saws the outer face thereof is constantly the same distance beyond the outside saw, so that the outside hoard cut off thereby will be of equal thickness throughout its entire'length.

'lhese and other features of my invention are hereinafter fully set forth and explained, and illustrated in the accompanying drawings, in which- Figure l is a top or plan view of my improved gang-saw mill. Fig. 2 is a side View in elevation of the same. Fig. 3 is a front view in elevation of the same with the feedrolls and base partly in section. Fig. 4 :is a vertical section of the frame, sash, and mechanism on the line n: a: in Fig. 3 looking in the direction of the arrow. Fig. 5 is an enlarged view in elevation of the side of the saw-carriage, illustrating the operation of the diagonal or cut roll mechanism thereof.

In the drawings illustratingmy invention, AA are the sides, and B B the base and top, of the frame of my improved gang-saw mill. In the upper part of this frame I mount a saw-sash C, which operates in the usual vertical guides a on the sides of the frame. This sash C, I make with a central brace or support D, which is firmly secured between the upper and lower girths C C2 of the sash C, so as to firmly support the central part thereof. against the strain of the saws c. Upon this central brace or stile D, I secure cutters or choppers CZ, which are adapted to cut orchop away any portions of logs or cants which Vwould contact with the support or brace D. For operating this saw-sash I mount a driving-shaft E on the base B 0f the frame, having the usual driving-pulley E on one end and a friction-pulley Egon the other tor driving the feed mechanism of the gang. On the central part of the shaft E in lieu of the ordinary U-shaped cranks I secure double eccentrics e e', the eccentrics c being preferably much smaller than the eccentrics e. These eccentrics are secured to the shaft close together, with the throws thereof opposite each other, and are preferably made integral with each other. From the eccentrics e pitmen F extend to the lower girth C2 of the sash C, and from the eccentrics c pitmen F' extend downward and connect with counterweights G, which swing upon a shaft G',

mounted in bearings g g at one side of the base B of the frame, as clearly illustrated in Figs. 2, 3, and 4. It will be observed that by means of this construction I am enabled to get the lines of strain upon the eccentrics e and e close together, while in the usual U- shaped-crank construction they are necessarily lseparated by the thickness of the arms of the cranks, and by this meansu I reduce the vibration of the shaft E, caused by the strain of the sash C and the counterweights G thereon,to a minimum and am enabled therefore to safely use a much smaller driving-shaft than is safe with the U-shapedcrank construction. Again, I preferably make the eccentrics e" approximately onehalf the diameter of the eccentrics e and proportionatelyincrease the weight of the counterweights G, which modification ofthe strncture tends to greatly reduce the strain and vibration of the driving-shaft E and at the same time reduces the length of the parts projecting below the base of the frame, while in no wise interfering with the successful operation of the counterbalanceweights in ceunterbalancing the sash G.

The feed-roll mechanism of my improved structure is generally of the usual construcltion, it consisting of a vertical shaft I, provided with a friction-roll I', adapted to contact with the face of the friction-disk E2. The shaft I is mounted at its lower end in a bearing 1', which is adapted to be moved toward and away from the friction-disk E2 when desired, and at its upper end in a sleeve t", mounted in a bearing i2, through which the shaft I is adapted to be moved vertically and with which it is connected by a spline and groove i3, and upon the sleeve t" there is a bevel-pinion J, which intermeshes with a bevel-gear feed-roll-driving wheel J,the shaft of which is provided with the usual pinion J2, intermeshing with the gear-wheels K on the ends of the feed-rolls K. For moving the shaft I up and down to Vary the speed of the feed mechanism I secure a grooved collar I2 to the shaft I, and extending from and pivoted to the side A of the frame there is an arm L, the end of which is bifurcated and tits the groove in the coliar I2, and through this arm L there is an adjusting-screw L with ahand-wheel Z thereon,by means whereof the outer end of the arm L and the shaft I can be raised and lowered as desired. The shaft I is also provided with a hand-wheel I3 for operating the same by hand when desired.

The press-roll yokes M are mounted upon removable vertical pins m fm., which .pass through supports a c on the side A A of the frame, and the press'roll yoke M is adapted to slide up and down thereon or be swung IIO n and supply-pipes n' leading thereto. y the piston-rods N', I pivot links n2, which excure cylinders N N, (see Figs. 3 and 4,) pro-y vided with fluid-actuated pistons and pistonrods N' and with the usual valve mechanism To tend to arms O, secured to rock-shafts O', mounted in the side frames A A'. In sleeves P, secured to each end of the rock-shaft O', there are telescoping arms, p, from which links p' extend to each end of and are removably pivoted upon studs at the ends of the press-roll yokes M, so that the press-roll yoke M and the press-rolls M' M can be moved up and down thereby; but when it is desirable to detach the links p from the press-roll yoke M it can readily be done by removing the loose pins m', after which the links p' can be detached from the press-roll yoke M. For moving the arms p in the sleeves Pon the rockshaft O', mounted in the sides A A of the frame, I provide transverse shafts Q, mounted in the sides A A' of the frame, and from arms Q' thereon links q extend to the links 3o p', so that the rocking of the shaft Q by means of the lever Q2 at the side A of the frame operates to shorten or lengthen the arms p and correspondingly increase or diminish the power exerted by the cylindersN N upon the press-roll yokes M. While Ihave thus shown and described the armsp on the rock-shaft O' asadjustable and prefer a construction of this character, yet I can secure such arms directly to the rock-shafts O' withoutprovidingforanyadjustmentofthelength thereof and obtain excellent results. Therefore I do not confine myself to the peculiar construction of rock-shaft arms shown and described. A

In constructing the saw-carriage of this mill I make it with the usual log orcant supporting rolls R, mounted in supports R' in the usual manner, and provide the carriage with the usual guides c at each side thereof; but between the supporting rolls R, I mount on pivoted bearings at one end thereof yokes S diagonally to the guides r, -as clearly shown in Fig. 1. In these yokes S, I mount spiked rolls S. Across the carriage I mount a transverse shaft T, provided with cams t t, upon which the free ends of the yokes S rest, which operates, when the shaft T is rotated, to raise and lower the rolls S', as is clearly illustrated in Fig. 5. At one side of the carriage the shaft T is provided with an operating-lever T', bymeans whereof the shaft T can be rotated as desired.

I have thus described the several parts of the mechanism and their functions so fully that it is believed further reference thereto is unnecessary. It is manifest, however, that many features of the invention herein shown and described may be modified in their construction wthout departing from the spirit of my invention. Therefore I do'not desire to limit myself to the exact construction and arrangement of parts of my structure herein shown and described.'

Having thus shown and described a convenient construction of mechanism which will enable others skilled in the art to which it appertains to utilize my invention, what I claim as new, and desire'to secure by Letters Patent of the United States, is-

1. The combination in a gang-saw mill, of a frame, a saw-sash mounted on guides therein, a driving-shaft mounted in the base of the frame, sash and counterweight eccentrics secured upon said shaft in contact with each other so as to operate in opposition to each other with a minimum vibration of the shaft, a pitman connecting the sash-eccentric with the sash, and a pitman extending downward from the counterweight-eccentric to and connecting with a counterweight, substantially as and for the purpose set forth.

2. The combination in a gang-saw mill, of

a frame, a sash mounted therein, a drivingshaft mounted in the base of the frame, counterweights below said shaft and secured upon arms pivoted to the base of the frame, dierential sash and counterweight eccentrics on said shaft immediately adjacent to each other and operating in opposition, a pitman extending from the sash-eccentric to the saw-sash,

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and a pitman extending from the counterweight-eccentric to the counterweight, substantially as and for the purpose set forth.

3. The combination in a gang-saw mill, of a frame, a sash mounted therein, a drivingshaft mounted in the base of the frame operating said sash, feed-roll mechanism operated by said driving-shaft, pressure-roll yokes carrying pressure-rolls mounted on said frame,

a cylinder mounted near the base of said frame, a fluid-'actuated piston in said cylinder, an arm on a rock-shaft in said frame, connected with said piston-rod, adjustable arms on each end of said rock-shaft, and links connecting the same with said pressure-roll yokes, substantially as and for the purpose set forth.

4. The combination with a gang-saw mill of a feedway comprising substantially log or cant carrying rolls, guides at the sides of the feedway, vertically-movable roll-supports in said feedway, rolls diagonally mounted in said vertically-movable roll-supports and mechanism for raising and lowering said roll-supports so as to bring the rolls carried thereby into or out of contact with logs or cants passing along said feedway and through the mill, substantially as and for the purpose set forth.

5. The combination with a gang-saw mill of a feedway comprising substantially log or cant carrying rolls, guides at the sides of the feedway, roll-supports pivoted at one end and vertically movable at' the other, diagonal cutting rolls mounted in said supports, and

IIC

means for raising and lowering the free ends l and cam-and-lever mechanism for raising and of said roll-supports, substantially as and for lowering the free ends of said yokes, subthe purpose set forth. stantially as and for the purpose set forth.

G. The combination with a gang-saw mill In testimony whereof I affix my signature 5 0f a feedway comprising substantially log or in presence of two witnesses.

cant carrying rolls, guides at the sides ot' the VILLIAM M WILKIN feedway, roll-supporting yokes pivoted at one of their ends in fixed bearings and having their \Vitnesses:

other ends vertically movable, spiked diago- II. M. STURGEON, xo nal or cutting rolls mounted in said yokes, F. J. BASSETT. 

